ATLANTA – Rain and fog in the East caused delays for holiday travelers heading home Monday after the long Thanksgiving weekend and threatened to cause a ripple effect of bottlenecks elsewhere.

Monitors in the terminals at New York's LaGuardia airport showed numerous canceled and delayed flights.

Arrivals there were also delayed up to three hours, said Steve Coleman, a spokesman for the Port Authority of New York and New Jersey. Delays at the metro area's Newark Liberty Airport averaged one hour and 37 minutes but New York's Kennedy International was not affected, Coleman said.

"I thought this would be an easier travel day," 12-year-old Maria Burgos said at LaGuardia, where she was waiting for a flight home to Miami after spending the holiday with relatives.

Arrival delays at Philadelphia International Airport averaged just over an hour, and threatened to worsen during the day, airport spokeswoman Phyllis Van Istendal said.

Security line waiting times at Hartsfield-Jackson Atlanta International Airport steadily improved during the morning Monday, but travelers there were expected to face growing problems later because of the weather-caused delays elsewhere, AirTran spokesman Dave Hirschman said.

"The bad news is that the Northeast has really been slammed today," he said.

Departure delays in the Northeast will mean late arrivals at Hartsfield-Jackson, he said. Travelers arriving in Atlanta may find that their connecting flights have already left, and it will be harder for them to catch later flights since most departing planes are 80 percent full.

"This is an extremely busy flying day, especially in the Northeast," Hirschman said. "When they fall behind early, it's nearly impossible to catch up as the day goes on. These delays are going to ripple throughout the network.

"We're delighted to see the rain," Hirschman said of the drought-stricken Southeast. "But it sure would have been great if we'd had one more day of drought."

Delta Air Lines also expected delays because of the poor weather in the Northeast, spokeswoman Susan Elliott said Monday.

"Some of our customers are inconvenienced because of delays at other airports, but for the most part we've got a lot of runway capacity here, plenty of gates, plenty of parking," he said Monday morning. "Throw good visibility on top of it, it adds up to a good Thanksgiving weekend."

At O'Hare International Airport, minor delays were reported Monday morning because of fog. About 237,000 passengers were expected to travel through the nation's second-busiest airport on Monday.

Some delays also were reported across Chicago at Midway Airport, mostly because of fog and low visibility at the airports farther east. About 73,000 travelers were expected at Midway on Monday.

AAA said its surveys indicated a record 38.7 million U.S. residents were likely to travel 50 miles or more for the holiday period of Wednesday through Sunday, up about 1.5 percent from last year. About 4.7 million were expected to fly, and about 31.2 million travelers were likely to drive in spite of rising gasoline prices, AAA said last week.